French election has investors globally on knife edge, with future of EU in the balance

The French presidential elections represent the greatest source of uncertainty for markets this year.

As a founding member of the European Union, the risk of the French electing a president who favors separation from the bloc amounts to a true existential threat for the European project. The risk posed is much more severe than that from Brexit, because the UK - already something of a reluctant partner - has its own currency, while France is a member of the euro.

Jean-Luc Mélenchon and Marine Le Pen, two of the four leading candidates, favor an exit from or dramatic renegotiation with the EU. Should either win the keys to the Élysée Palace and follow through on their threats of a Frexit, support for the EU across the continent would likely fracture, making its continued existence untenable.

The situation is made more difficult by a lack of visibility on the ultimate outcome after two rounds of voting - the first on April 23, followed by a runoff between the top two candidates in May 7, should no clear winner emerge from the first round.

Four of the eleven candidates are polling within margins of error of each other. Moreover, polling is volatile, with candidates rising and falling quickly and regularly. There is also a ge......................